Duncan I of Scotland

[8] An earlier source, a variant of the Chronicle of the Kings of Alba (CK-I), gives Duncan's wife the Gaelic name Suthen,[9] and John of Fordun suggests that she may have been a relative of Siward, Earl of Northumbria.

[10] This differs from the review by Frederic van Bossen who wrote in 1688 that King Duncan was twice married, his first wife being Wonfrida (Unfrida) the daughter of Gigurt (Earl Siward?)

The eldest, Malcolm III (Máel Coluim mac Donnchada) was king from 1058 to 1093 after assassinating and usurping Lulach, Macbeth's stepson.

In context — "dukes of Francia" had half a century before replaced the Carolingian kings of the Franks and in England the over-mighty Godwin of Wessex was called a dux — this suggests that Macbeth may have been the power behind the throne.

The 14th century chronicler John of Fordun would write that Duncan's wife was a kinswoman of the Anglo-Danish Siward, Earl of Northumbria, who would help restore her son Malcolm to the throne.

In self-defence Macbeth meets him in battle and wounds him, and he dies of bleeding, for he is bad-blooded, or Haemophilia C. In the animated television series Gargoyles he is depicted as a weak and conniving king who assassinates those who he believes threaten his rule.